Answer these questions to help you choose the proper construction laser...

Will the laser level be used indoors, outdoors, or both?

To use the laser visually for interior construction, choose a level tool with a highly visible beam, either ~635nm red laser or ~530nm green laser. ou will need a laser level detector for outdoor work, as even a highly visible green laser will be lost in daylight. Laser construction levels designed for interior work will also feature variable rotation speed or beam scanning to maximize visibility.

Can the laser level be disturbed by laborers, live traffic, or heavy equipment?

If you work on large, busy sites, self leveling is an absolute must. A self leveling construction laser corrects for slight disturbances from wind or vibration, and will shut off for greater disturbances. Manually leveled lasers must be periodically checked and re-leveled to assure accurate results. This is fine for small, well controlled sites such as house foundations, or deck and landscaping work. Self leveling lasers are a must for larger jobs and commercial buildings. Self leveling is achieved by either a servo motor system or a compensator, both which can provide similar accuracy. If you are placing the laser level on a 3 metre tripod for machine control work, or up on wall angle for suspended ceiling installation, a servo leveled laser is handy because it does not have to be rough leveled. Compensator leveling systems have to be roughed-in before they can self level and are simpler electronically.

How much accuracy do you need in your construction laser level?

Rotary construction laser accuracy starts on the low end at about +/- 6mm per 30m for inexpensive manually leveled products, and increases to as fine as ±7 arc sec (1mm per 30m) for self leveling lasers. Error increases with distance from the laser transmitter. If a laser's accuracy is ±1mm at 30m, it is ± 2mm at 60m and ± 4mm at 120m. The best accuracycomes from working as close as possible to the laser level.

Do you need a laser level tool that can also project a slope?

Construction lasers for precision slope (storm sewers or airport runways) have mechanical or digital counters that enable entry of slope in increments of .01% or better. For less precise applications such as drainage ditches and drive ways there are self-leveling lasers capable of manual "slope matching".

Do you need additional features, such as vertical alignment, or 90º layout?

If you need to perform layout and alignment tasks that go beyond the basic level tools, there are a variety of features available. There are laser construction level tools capable of projecting a vertical plane of laser light for layout, or plumb alignment. Laser level tools are great for taking base lines or layout points and transferring them to a ceiling, or upper floor. There are models with a plumb laser spot that forms a 90º reference to the plane of laser light. That 90º reference can be used for square layout, or to transfer single points up and dead vertical. This is really handy on a windy high-rise job and for special needs like elevator shaft control points.

Frequently asked questions:

The L4.7 construction lasers is described as self leveling or automatic. How come I have to turn leveling screws?

These construction laser models self level via wire hung compensators. These are gravity pendulum leveling mechanisms that must be rough leveled. Once the instrument is in its self leveling range, the compensator makes sure that the beam is level. The term "automatic" derives from automatic optical levels which employ compensators for self leveling. These autolevels also have to be rough leveled. Servo motor leveling systems have a wider self leveling range and allow the user to turn the laser on without having to turn leveling screws.

Which self leveling system is better, servo motor or compensated?

Each system has its pluses and minuses. Servo systems have the appeal of driving the laser to level without the operator turning leveling screws. However, a compensated self leveling laser can be up and running just as fast as a servo system. Well designed servo systems and compensated systems both provide accurate and reliable results. For grade checking and concrete work, compensated systems have been the mainstay for many years as they provide better temperature and vibration compensation than all but the most expensive servo systems. If the laser is going to be used in a situation where it is inconvenient to turn leveling screws, (up on a 3-4 metre tripod for machine control), a servo system would be preferable.

Can I use a visible construction laser outdoors without a receiver?

A rotary laser will have to be used with a receiver outdoors in the sun. Safety regulations do not permit a beam powerful enough to be visible when rotating out in sunlight. If you stop the rotating beam and shine it onto a shaded target, you can use it as a reference, but this is not that convenient.

How often should my laser be calibrated?

Lasers should be calibrated when they are not shooting their specified accuracy. We suggest checking calibration regularly, at least every 6 months, or immediately if the unit has been treated roughly.

Can I set a grade or slope into the laser?

You can set a precise slope with the AS2 and AS2 Magnum lasers. You can “slope match” between existing elevations with both Alpha models and the L6 laser. You cannot set a slope with the L4.7, or L4.7 Magnum lasers. The L3 laser features a manual vial with markings for 1, 2, 3, or 4% slope.

Where can I get my construction laser serviced?

Almost any laser or survey instrument service center can calibrate our lasers, or the user can do so if he/she so desires. Many of our 400+ dealers in the US have some service capabilities ranging form calibrating lasers up through full repairs.

What kind of tripod do I need for my laser?

Our lasers fit tripods with a 5/8 x 11 coarse thread. Dome or flat head tripods can be used. A flat head tripod will allow the user to check calibration easily out in the field whilst a dome head tripod allows the L4.7 and L4.7 Magnum to be levelled without using the levelling screws.

Can the laser light hurt my eyes?

The maximum power output for any construction laser is less than 5 milliwatts. A milliwatt is one thousandth of a watt. No special precautions need be taken with an invisible beam laser. Visible beam lasers should be set so they are not flashing in anyone's eyes because the light is very bright and can be annoying. Having the beam flash in one's eyes occasionally will not do any damage, but will be irritating in the same fashion as a camera flash.

Can your construction lasers be used for turning angles?

Our visible beam L4.7 Magnum, L6 and L3 lasers have fixed plumb spots that provide a 90 degree reference laser beam relative to the rotating beam when the laser is in its vertical mode. This is only easily used indoors out of the sun.

Can I use a laser receiver to pick up the plumb spot?

Most laser receivers are looking for a laser spot flashing across their photocells and will not respond to a stationary laser spot. The Spectra Precision UL633 is the only laser system on the market that is capable of picking up a stationary spot. Using a special receiver the dot can be detected up to 80m away.

What happens if my construction laser is rained on?

Pro Shot lasers are water and dust resistant. Simply dry the laser off before it is stored.

For further information Please visit: http://www.lasersurveyingequipment.com.au/technical-articles/reference-guides/73-proshot-laser-decision-guide.html